Squashed 'third_party/flatbuffers/' changes from d6a8dbd26..338393f85

338393f85 Documentation updates for Optional Scalars (#6014) (#6270)
c27bc2d76 [C++] Add ParseJson(), Parser(Parser&&), update fuzzers (#6284)
bc518a512 Fixed FlexBufferBuilder asserting on duplicate keys
100c59054 Added a few more paths for auto labeler (#6281)
e58c18244 Add --require-explicit-ids to require explicit ids (#6277)
69a8b2a57 idl_gen_json_schema.cpp: Changed generation of array element types (#6253)
25eba6f35 fix typo (#6280)
e1f0f75ba Updated Ms build Action to fix build issue (#6279)
faeb04fbe Add type annotation to unspecified array (#6264)
537212afe [Swift] Adds a format file and reformats the swift project (#6250)
6764f25d9 Adds a fix for enum generation (#6263)

Change-Id: I716bd4d2521fb0a673e50a699cef761e042052b2
git-subtree-dir: third_party/flatbuffers
git-subtree-split: 338393f854eb5ba24761a22cd9316ff5cee4eab0
diff --git a/include/flatbuffers/idl.h b/include/flatbuffers/idl.h
index a28745f..6afdc7a 100644
--- a/include/flatbuffers/idl.h
+++ b/include/flatbuffers/idl.h
@@ -601,6 +601,9 @@
 
   MiniReflect mini_reflect;
 
+  // If set, require all fields in a table to be explicitly numbered.
+  bool require_explicit_ids;
+
   // The corresponding language bit will be set if a language is included
   // for code generation.
   unsigned long lang_to_generate;
@@ -661,6 +664,7 @@
         filename_extension(),
         lang(IDLOptions::kJava),
         mini_reflect(IDLOptions::kNone),
+        require_explicit_ids(false),
         lang_to_generate(0),
         set_empty_strings_to_null(true),
         set_empty_vectors_to_null(true) {}
@@ -800,6 +804,11 @@
     }
   }
 
+#ifdef FLATBUFFERS_DEFAULT_DECLARATION
+  Parser(Parser&&) = default;
+  Parser& operator=(Parser&&) = default;
+#endif
+
   // Parse the string containing either schema or JSON data, which will
   // populate the SymbolTable's or the FlatBufferBuilder above.
   // include_paths is used to resolve any include statements, and typically
@@ -814,6 +823,8 @@
   bool Parse(const char *_source, const char **include_paths = nullptr,
              const char *source_filename = nullptr);
 
+  bool ParseJson(const char *json, const char *json_filename = nullptr);
+
   // Set the root type. May override the one set in the schema.
   bool SetRootType(const char *name);
 
@@ -941,6 +952,7 @@
                                     const char **include_paths,
                                     const char *source_filename,
                                     const char *include_filename);
+  FLATBUFFERS_CHECKED_ERROR DoParseJson();
   FLATBUFFERS_CHECKED_ERROR CheckClash(std::vector<FieldDef *> &fields,
                                        StructDef *struct_def,
                                        const char *suffix, BaseType baseType);